Preprints
Filtering by Subject: Physical Sciences and Mathematics
Autonomous Passage Planning for a Polar Vessel
Published: 2022-08-31
Subjects: Artificial Intelligence and Robotics, Computer Sciences, Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Other Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sustainability
We introduce a method for long-distance maritime route planning in polar regions, taking into account complex changing environmental conditions. The method allows the construction of optimised routes, describing the three main stages of the process: discrete modelling of the environmental conditions using a non-uniform mesh, the construction of mesh-optimal paths, and path smoothing. In order to [...]
A review of coarse mineral dust in the Earth system
Published: 2022-08-31
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Mineral dust particles suspended in the atmosphere span more than three orders of magnitude in diameter, from less than 0.1 µm to more than 100 µm. This wide size range makes dust a unique aerosol species with the ability to interact with many aspects of the Earth system, including radiation, clouds, hydrology, atmospheric chemistry, and biogeochemistry. This review focuses on coarse and [...]
Fingerprinting construction sand supply-networks for traceable sourcing
Published: 2022-08-31
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Globally increasing demand for construction sand needs to be met with transparent and responsible supply-networks. Currently, there are no scalable methods for tracing construction sand distribution without direct observation. We examined sand “fingerprinting” as a potential tool to trace construction sand supply-networks from “source to sink” in a case study from Texas, USA. Both natural bulk [...]
Subglacial hydrology modeling predicts high winter water pressure and spatially variable transmissivity at Helheim Glacier, Greenland
Published: 2022-08-26
Subjects: Engineering, Physical Sciences and Mathematics
Sliding velocity of glaciers is influenced by water pressure at the bed. Subglacial hydrology models are helpful for gaining insight into basal conditions, but models depend on several unconstrained physical parameters, and reproducing elevated water pressures in winter has been a challenge. We eliminate terms in the SHAKTI model that rely on uncertain parameters and apply this model to Helheim [...]
Fusing physics-based and data-driven models to forecast and mitigate landslide collapse
Published: 2022-08-26
Subjects: Engineering, Physical Sciences and Mathematics
Deep-seated landslides represent one of the most devastating natural hazards on earth, typically creeping at inappreciable velocities over several years be- fore suddenly collapsing with catastrophic speeds. They can have detrimental consequences to society, causing fatalities and prone to affect transportation infrastructures. In this study, we validate that monitoring the basal temperature of a [...]
A genetic model of the magnetite-apatite deposits on El Laco volcano by extrusion of iron-rich melt
Published: 2022-08-25
Subjects: Dynamical Systems, Earth Sciences, Fluid Dynamics, Geochemistry, Geology, Numerical Analysis and Scientific Computing, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
Magnetite-apatite deposits are important sources of iron and other metals. A prominent exam- ple are the magnetite lavas at the El Laco volcano, Northern Chile. Their formation processes remain debated. Here, we test the genetic hypothesis that an Fe-rich melt separated from silicate magma and ascended along collapse-related fractures. We complement recent analy- ses with thermodynamic modelling [...]
Lithology, pore-filling media, and pore closure depth beneath InSight on Mars inferred from shear wave velocities
Published: 2022-08-25
Subjects: Physical Sciences and Mathematics
We quantify the volume and distribution of water, cement, sediments, and fractured rocks within the Martian crust beneath NASA's InSight (Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport mission) lander by using rock physics models to interpret shear wave velocities Vs measured from InSight data. The models assume that Mars' crust comprises sediments and fractured [...]
Groundwater deeper than 500 m contributes less than 0.1% of global river discharge
Published: 2022-08-25
Subjects: Physical Sciences and Mathematics
Groundwater is one of the largest reservoirs of water on Earth but has relatively small fluxes compared to its volume. This behaviour is exaggerated at depths below 500 m, where the majority of groundwater exists and where residence times of millions to even a billion years have been documented. However, the extent of interactions between deep groundwater (>500 m) and the rest of the terrestrial [...]
The salmonid and the subsurface: Hillslope storage capacity determines the quality and distribution of fish habitat
Published: 2022-08-25
Subjects: Life Sciences, Physical Sciences and Mathematics
Water in rivers is delivered via the critical zone that mantles landscapes. Consequently, the success of stream-rearing salmonids depends on the structure and resulting water storage and release processes of this zone. Physical processes below the land surface (the subsurface component of the critical zone) ultimately determine how landscapes ‘filter’ climate to manifest ecologically significant [...]
Thermal forcing expected to modulate convection in a mechanically forced stationary wave
Published: 2022-08-16
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Physical Sciences and Mathematics
This is a reply to the comment by Lofverstrom and Thirumalai on our publication in Nature. That comment and this reply underwent peer review at Nature, and Nature declined to publish the exchange
Algorithm theoretical basis document for GEDI footprint aboveground biomass density
Published: 2022-08-14
Subjects: Engineering, Physical Sciences and Mathematics
The Global Ecosystem Dynamics Investigation (GEDI) lidar is a multibeam laser altimeter on the International Space Station (ISS). GEDI is the first spaceborne instrument designed to measure vegetation height and to quantify aboveground carbon stocks in temperate and tropical forests and woodlands. This document describes the algorithm theoretical basis underpinning the development of the GEDI [...]
Understanding recent tropospheric ozone trends in the context of large internal variability: A new perspective from chemistry-climate model ensembles
Published: 2022-08-12
Subjects: Physical Sciences and Mathematics
Observational records of meteorological and chemical variables are imprinted by an unknown combination of anthropogenic activity, natural forcings, and internal variability. With a 15-member initial-condition ensemble generated from the CESM2-WACCM6 chemistry-climate model for 1950-2014, we extract signals of anthropogenic (‘forced’) change from the noise of internally arising climate [...]
Validating mechanistic models of fluid displacement during imbibition
Published: 2022-08-11
Subjects: Physical Sciences and Mathematics
Pore-scale modelling is an important tool to improve our understanding of multiphase flow in porous media. Slow fluid invasion is commonly modelled using quasi-static pore network models (PNM). These models simulate the invasion in a network of simplified pores and throats by invading network elements in order of the quasi-static “invasion” capillary pressure needed for the invading fluid to [...]
A note on climate science and climate policy
Published: 2022-08-10
Subjects: Physical Sciences and Mathematics
A short note on climate science and climate policy, discussing planning vs acting, and the differences between decision making and regret under uncertainty and in a deterministic environment.
SubZero: A Sea Ice Model with an Explicit Representation of the Floe Life Cycle
Published: 2022-08-08
Subjects: Physical Sciences and Mathematics
Sea ice dynamics exhibit granular behavior as individual floes and fracture networks become particularly evident at length scales O(10--100) km and smaller. However, climate models do not resolve floes and represent sea ice as a continuum, while existing floe-scale sea ice models tend to oversimplify floes using discrete elements of predefined simple shapes. The idealized nature of climate and [...]